Infrastructure
Here I mean the infrastructure needed and provided to make Open Source.
An Open Source project typically only needs a few fundamentals:
- a website
- an issue tracker
- source code version control and management
- communication channels
With those, a project can flourish. Sure, you can add other services too to make things even greater, but good projects have succeeded with only these 4.
In all those four areas, infrastructure has greatly improved over the last three decades.
Website
You no longer have to run a physical machine and master your own configs to make a web server work. You still can if you want, but these days there are countless of ways to use others' machines and others' services with virtual machines, co-hosting and what not. At low cost.
It is even usually easy and cheap to register a domain for this to get your personal name on the site.
Issue tracker
These days many (most?) projects go with a service provider that hosts and offers a whole selection of project management services in the same place in an integrated fashion. GitHub and Gitlab being two popular and known providers.
Setting up a good and productive issue tracker for your project used to be complicated. It is not anymore.
Version control
RCS was replaced by CVS which was replaced by Subversion for a short while until the distributed version control systems took off.
Today, git is really the version control champion and we are all so much better off now than we ever were before.
Distributed development has never been done with better tools than now.
Communication
When I started working in Open Source, mailing lists and IRC were just about the only two options.
Since then, the world has exploded with different communication options. The current challenge is rather that there are so many options and alternatives that you risk drowning or maybe that your users get spread out with just a tiny fraction using each available service.
The chat and video platforms of today are beyond what we could even dream of in the Open Source projects of the 1990s.